We discuss the X-ray properties of the interacting system Arp 284 , consisting of the active nuclear starburst galaxy NGC 7714 and its post-starburst companion NGC 7715 .
A morphological signature of the interaction , thought to have started < 100 Myr ago , is an asymmetric stellar ring dominating the intensity profile of NGC 7714 in the inner disk ( \sim 2 exponential scale lengths ) .
In agreement to previous Einstein -data our ROSAT PSPC exposure shows the X-ray emission of Arp 284 to be confined to NGC 7714 .
The bulk of the intrinsic X-ray luminosity in the ROSAT 0.1–2.4 keV band can be accounted for by thermal emission from hot ( \sim 5 \times 10 ^ { 6 } K ) gas and amounts to \sim 2 - 4 \times 10 ^ { 41 } { erg s ^ { -1 } } .
Follow-up observations with the ROSAT HRI revealed two distinct extended emitting regions contributing to the X-ray luminosity in NGC 7714 .
The more luminous of them ( L _ { X } \la 2 \times 10 ^ { 41 } { erg s ^ { -1 } } ) coincides with the central starburst nucleus and can be explained this way .
The fainter one ( L _ { X } \sim 8 \times 10 ^ { 40 } { erg s ^ { -1 } } ) is located \sim 20 ″ off-center and does not have any conspicuous optical counterpart .
It is , likely , located at the borderline between the stellar ring and a massive ( > 10 ^ { 9 } { M _ { \odot } } ) H I -bridge further to the east possibly intersecting NGC 7714 .
The H I and X-ray morphology and the extensive starburst nature of the nuclear energy source suggest different scenarios for the formation of the eastern emission spot .
The possibilities of ( i ) collisional heating of the outlying gas by a starburst-driven nuclear wind and ( ii ) infall of H I -clouds from the bridge onto the disk of NGC 7714 are discussed .